Upgrade to remove ads
Chemistry Chapter 4-5 New Vocabulary
Terms in this set (48)
Dalton's atomic theory
States that matter is composed of extremely small particles called atoms; atoms are invisible and indestructible; atoms of a given element are identical in size, mass, and chemical properties; atoms of a specific element are different from those of another element; different atoms combine in simple whole-number ratios to form compounds; in a chemical reaction, atoms are separated, combined, or rearranged.
the smallest particle of an element that retains all the properties of that element; is electrically neutral, spherically shaped, and composed of electrons, protons, and neutrons.
radiation that originates from the cathode and travels to the anode of a cathode-ray tube.
in an electrochemical cell, the electrode where reduction takes place.
a negatively charged, fast-moving particle with an extremely small mass that is found in all forms of matter and moves through the empty space surrounding and atom's nucleus.
the extremely small, positively charged, dense center of an atom that contains positively charged protons and neutral neutrons.
a subatomic particle in an atom's nucleus that has a positive charge of 1+.
a neutral, subatomic particle in an atom's nucleus that has a mass nearly equal to that of a proton.
the number of protons in an atom.
atoms of the same element with different number of neutrons.
the number after an element's name, representing the sum of its protons and neutrons.
atomic mass unit (amu)
one-twelfth the mass of a carbon-12 atom.
the weighted average mass of the isotopes of that element.
the process in which some substances spontaneously emit radiation.
the rays and particles--alpha and beta particles and gamma rays--that are emitted by radioactive materials.
a reaction that involves a change in the nucleus of an atom.
a spontaneous process in which in which unstable nuclei lose energy by emitting radiation.
radiation that is made up of alpha particles; is deflected toward a negatively charged plate when radiation from a radioactive source is directed between two electrically charged plates.
a particle with two protons and two neutrons, with a 2+ charge; is equivalent to a helium-4 nucleus;and is emittied during radioactive decay.
a type of equation that shows the atomic number and mass number of the particle involved.
radiation that is made up of beta particles; is deflected toward a positively charged plate when radiation from a radioactive source is directed between two electrically charged plates.
a high-speed electron with a 1- charge that is emitted during radioactive decay.
high-energy radiation that has no electrical charge and no mass , is not deflected by electric or magnetic fields, usually accompanies alpha and beta radiation, and accounts for most of the energy lost during radioactive decay.
a form of energy exhibiting wavelike behavior as it travels through space; can be described by wavelength, frequency, amplitude, and speed.
the shortest distance between equivalent points on a continuous wave; is usually expressed in meters, centimeters, or nanometers.
the number of waves that pass a given point per second.
the height of a wave from the origin to a crest, or from the origin to a trough.
includes all forms of electromagnetic radiation; the types of radiation differ in their frequencies and wavelengths.
the minimum amount of energy that can be gained or lost by an atom.
6.626 x 10(-34) Jxs, where J is the symbol for the joule.
a phenomenon in which photoelectrons are emitted from a metal's surface when light of a certain frequency shines on the surface.
a particle of electromagnetic radiation with no mass that carries a quantum of energy.
atomic emission spectrum
a set of frequencies of electromagnetic waves given off by atoms of an element; consists of a series of fine lines of individual colors.
the lowest allowable energy state of an atom.
the number assigned to each orbit of an electron.
de Broglie equation
predicts that all moving particles have wave characteristics and relates each particle's wavelength to its frequency, its mass, and Planck's constant.
Heisenberg uncertainty principle
states that it is not possible to know precisely both the velocity and the position of a particle at the same time.
quantum mechanical model of the atom
an atomic model in which electrons are treated as waves; also called the wave mechanical model of the atom.
a three-dimensional region around the nucleus of an atom that describes and electron's probable location.
principal quantum number
assigned by the quantum mechanical model to indicate the relative sizes and energies of atomic orbitals.
principal energy level
the major energy levels of an atom.
the energy levels contained within a principal energy level.
the arrangement of electrons in an atom, which is prescribed by three rules---the aufbau principle, the Pauli exclusion principle, and Hund's rule.
states that each electron occupies the lowest energy orbital available.
Pauli exclusion principle
states that a maximum if two electrons can occupy a single atomic orbital but only if the electrons have opposite spins.
states that single electrons with the same spin must occupy each equal-energy orbital before additional electrons with opposite spins can occupy the same orbitals.
the electrons in an atom's outer-most orbitals; determine the chemical properties of an element.
consists of an element's symbol, representing the atomic nucleus and inner-level electrons, that is surrounded by dots, representing the atom's valence electrons.
YOU MIGHT ALSO LIKE...
chapters 4 and 5 Chemistry Terms
Unit 2 Vocabulary
Chemistry: Chapter 3 test
Sara Salyers - Chemistry Chapter 4 Vocabulary
OTHER SETS BY THIS CREATOR
HSB EXAM 3
Literary Terms #4